1Includes workers in the private nonfarm economy except those in private households, and workers in the public sector, except the federal government. See "Technical note" for further explanation.

2The 10th, 25th, 50th, 75th, and 90th percentiles designate position within each published series. For example, at the 50th percentile or median, half of participating workers pay the same as or more than the premium shown, and half pay the same as or less than the premium shown. At the 25th percentile, one-fourth of participating workers pay the same or less than the premium shown. The remaining percentiles follow the same logic.